Is It REALLY A Best Practice In Programming

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dcisive

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I was wondering if it's true that you absolutely CAN ignore and delete frequencies that are on a Site that are NOT RED or BLUE. What will happen if anything if you delete those other frequencies listed in that Site. For example there are probably a dozen or more on the Salt Lake City Simulcast, but only several are RED or Blue. Could this potentially speed up the process of scan locks or does it have no effect or what effect WOULD it have to delete those non RED and BLUE frequencies. Thanks big time
 

kma371

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Depending on what scanner you have, you ONLY need the red and blue (control and alternate). Those are the only freqs on the system that transmit data, which you need.
 

kma371

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Yes for that scanner you only need the control and alternate control channel frequencies, so you should be fine.
 

drdispatch

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You only need the control channels & alternates as a minimum, and depending on how many sites you are scanning, you may see a decrease in your scan speed, but there is a trade-off. If you only have the control channels/alternates programmed, and the site goes into "fail-soft" mode, you will miss traffic if one of the voice channels is the only repeater operating. Also, control channels can/do change occasionally; you've got to watch the DB closely to catch that.

IMO, it's easier to just let Sentinel load all of a site's frequencies, because the scanner will only linger on the active control channel. I'd rather spend a few extra milliseconds scanning non-control channel frequencies than end up missing a control channel change in the DB and thereby miss all that site's traffic without even knowing it.

It all comes down to user preference, and the disclaimer: "Your mileage may vary".
 

jonwienke

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IMO it's a pointless optimization. Browsing extra freqs to find a control channel adds a few milliseconds per freq, vs a full second or so of dwell once it finds an active CC. The additional scan time is negligible, so it's better to cover the bases in case the system switches control channel freqs on you.
 

UPMan

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Note that the above does not apply to LTR, DMR, or EDACS systems. For those, you must enter all frequencies.
 

kma371

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If you only have the control channels/alternates programmed, and the site goes into "fail-soft" mode, you will miss traffic if one of the voice channels is the only repeater operating.

Kind of a moot point because if you programmed it as a trunked system, which you surely would have, the scanner would only be looking for a data channel and not voice.

The best way to listen to a system if it happened to go into failsoft mode, would be by programming all voice channels as a conventional system and I don't think most people do that.
 

sparklehorse

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IMO it's a pointless optimization. Browsing extra freqs to find a control channel adds a few milliseconds per freq, vs a full second or so of dwell once it finds an active CC. The additional scan time is negligible, so it's better to cover the bases in case the system switches control channel freqs on you.

I've found this to be an unwarranted concern. I'm sure in some rare situations system techs can and will change a primary or alternate control channel to a different frequency, one that is not listed as such in the RR database. But I think that is a very unusual occurrence. I know on my local Motorola 800MHz analog Smartzone system the control channel frequency has not changed in at least 15 years. In fact, I've never even seen one of the alternate frequencies used. And if the techs did make a big change like that, switching to a hitherto unlisted control, or alt cc frequency, a person would notice pretty quickly as their scanner would suddenly go dead. Basically, as long as your radio is purring along with system traffic, you can rest assured that you have the necessary control frequencies programmed for said system, and nothing else is needed.

.
 

dcisive

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I went ahead and deleted all the channels other than the control and "blue" backup frequencies in my Site's listings. Hopefully it will be just fine.
 

tampabaynews

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In my opinion, it is best practice to program all the frequencies in the system or site. I can't tell you how many threads I've seen where people ask "what's going on" and the issue was they didn't program all the frequencies and the control channel changed to something other than primary or alternate.

The database is user generated and not always 100% accurate. Provided you're in an area with great reception, programming all the frequencies shouldn't cause any problems. The time in acquiring the control channel should only come into play when you either turn on the scanner, enable the system, or venture within range. Otherwise, the scanner should lock on the CC until it is lost.
 

sparklehorse

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<snip> The time in acquiring the control channel should only come into play when you either turn on the scanner, enable the system, or venture within range. Otherwise, the scanner should lock on the CC until it is lost.

Even when you are parked on only one system, the Uniden scanners will drop their lock on the control channel once about every 1.5 seconds. This is for something Upman has described as a housekeeping sweep. Granted, this sweep only lasts a few mili-seconds, but the radio still has to go back and re-aquire the control channel when the sweep is complete. Having as few frequencies as possible reduces the number of channels it has to examine to find the active CC. Increasing the dwell time setting forces the scanner to make this sweep less often, but that can be counter productive if you are scanning multiple systems.

.
 

ofd8001

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You only "NEED" to have control channel frequencies. It is "NICE" to have all the others, just in case the database is missing an alternate control channel or as noted above, that rare occasion where some other frequency ends up becoming a control channel.

Given the amount of available memory for a Favorites List in this line of scanners, there really is no downside to programming all the frequencies. For older models, such as in the x96 line, that could be a different story because memory is more limited.

There certainly is no harm in retaining the frequencies. Delays are so slight to be noticeable.

The "Fail Soft" situation is a whole different creature. That's where a trunked system controller fails and the system goes into a pre-configured arrangement where all frequencies are used like a conventional system. However you must create a separate system (set up as a conventional system) in order to monitor a trunked system that goes into Fail Soft. You would Avoid that separate system until the Fail Soft situation occurs.
 

tampabaynews

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Even when you are parked on only one system, the Uniden scanners will drop their lock on the control channel once about every 1.5 seconds. This is for something Upman has described as a housekeeping sweep. Granted, this sweep only lasts a few mili-seconds, but the radio still has to go back and re-aquire the control channel when the sweep is complete. Having as few frequencies as possible reduces the number of channels it has to examine to find the active CC. Increasing the dwell time setting forces the scanner to make this sweep less often, but that can be counter productive if you are scanning multiple systems.

.

Following the housekeeping sweep, the scanner will try the last received control channel first before it checks all other frequencies.
 
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